Monday, May 16, 2016

With California ballots arriving in the mail, I was about to urge San Francisco Bay Area voters to support Measure AA to provide funding to protect and restore the Bay, at which point I should probably disclose that my new employer also supports Measure AA. So, my personal note is that I joined the Bay Area environmental organization Greenbelt Alliance this month, as Program Director working on open space protection - natural habitats, ranchlands, and farmlands.

Greenbelt promotes the right growth in the right place, so within Bay Area cities it promotes housing, particularly affordable housing, access to public resources and good transportation, while it also works to prevent our region's cities from sprawling and merging. Climate change is a cross-cutting issue inside and outside of cities, as is water.

My position is somewhat similar to an old one I had at another environmental organization when I first came to Rabett Run in 2011, although this is at a bigger organization with a broader scope. Still, my work there is to represent the organization while my fun here at Eli's is to spout my own nonsense. To keep the distinction I probably won't talk about Greenbelt's issues all that much here, except on occasion when it's really important. Protecting and restoring San Francisco Bay is really important.

Of specific importance to climate activists, many of the old salt ponds ringing the Bay and diked off from it have sunk in elevation. If they are restored before sea level rises too much, then emergent, tidal wetland vegetation can anchor in the mud, catch sediment, and possibly keep pace with sea level changes. If it's too late then even when opened to tidal action, the salt ponds become deep, open water areas with little or no sediment accumulation and the wetlands never come back.

I've been out to some tidal wetland restoration projects in the Bay, and they're great, with some endangered species (a bird and a mouse) moving into habitat that didn't exist a few years earlier. That success can be replicated, beginning with the vote on this measure.

9 comments:

Greenbelt issues are always very important.Greenbelts around SF Bay and Sac. Delta are a little more important.

I do not worry about any particular species as ecosystems will change as things warm, but we need (larger) tidal marsh areas where the new ecosystems can develop. It is the only way that we can keep a fish population in the Bay/Delta as things warm up.

Oh goodness. Have you looked under the hood on this one, Brian? A few general points:

Wetlands can grow vertically, but only if they have a sediment supply. Most of the Bay wetlands don't have one.

Per the science report from October, most wetlands will be inundated within this century, and that's assuming relatively modest sea level rise. I'm not saying it's not worth doing some wetland restoration anyway, but the yes campaign has been entirely silent on this point. The only options to avoid this are continued fill, which has sharp limits, and upland retreat, about which the proposal is astoundingly silent.

The science report isn't silent about it, and e.g. in my local area envisions extensive new tidal lands in the form of Bay Farm Island and assorted adjacent low-lying areas as sea level rise has its inexorable way. That's some expensive real estate.

Politically, the thing seems like a Silicon Valley Leadership Group scam with a bit of environmental window-dressing. It looks like on the order of 60% of the money could go to the Silicon Valley shoreline. Why not just ask them to pay for those improvements directly?

The horizontal levee concept, which will apparently be applied extensively in places like the Silicon Valley shoreline, seems like a hostage to fortune. The idea is that the levee itself can be made substantially shorter since an area of wetland in front of it will protect against storm surge and wave action. So when sea level does what sea level is going to do, do we replace all the levees or desperately try to keep shoveling soil in front of them? Sounds more and more expensive.

To add some context, the ides for this proposal was formulated before the science on sharp near-term sea level rise started coming in. In my direct experience, the type of government body that's in charge of the plan has a very, very hard time shifting gears in the face of new evidence.

And speaking of sea level rise, there's more bad news today. I suspect all of this is headed toward several meters of SLR rather closer to 2050 than 2100, which within the next few decades will wreck nearly everything this proposal will build.

Willard, as I tried to say the science report is really quite at odds with the proposal. In addition there's the factoid about wetlands being able to grow vertically without a significant sediment flow, which has never had scientific support. IIRC that can happen over very long time scales via the vegetative growth and die-back cycle, but it's not something that can keep up with SLR.

Would these be the people to start working at cleaning out the stuff that we don't want in our future wetlands, like oil and gasoline tanks and leaded paint and etcetera, while the lots are still not yet underwater? I wonder if this anticipation of sea level rise has given new meaning to 'underwater mortgage' in the loan industry yet.

I have friends about three feet above high tide level who refer to their house as their future "Crab Shack" anticipating its becoming bayshore property within their lifetimes. They remodeled with a very tall and sturdy first floor that's mostly big storage.

That stuff is included, Hank. Obviously the old landfills ate going to be a big issue (they're capped, but those caps weren't designed for inundation), and it will be interesting to see how they propose to remediate those without breaking the bank.

Steve - half the money will be allocated by population. The SF Bay Restoration Authority oversees the rest - I don't see Silicon Valley having the pull to seize the lion's share.

Horizontal levees are a great idea. Whether they'll be enough to handle the worse SLR scenarios over 50 years might be another question, but they'll still put us in a better position than doing nothing. I'm quite confident about that issue. Beyond 50 years is a lot to ask of any public works project.

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Eli Rabett

Eli Rabett, a not quite failed professorial techno-bunny who finally handed in the keys and retired from his wanna be research university. The students continue to be naive but great people and the administrators continue to vary day-to-day between homicidal and delusional without Eli's help. Eli notices from recent political developments that this behavior is not limited to administrators. His colleagues retain their curious inability to see the holes that they dig for themselves. Prof. Rabett is thankful that they, or at least some of them occasionally heeded his pointing out the implications of the various enthusiasms that rattle around the department and school. Ms. Rabett is thankful that Prof. Rabett occasionally heeds her pointing out that he is nuts.